For the most part, waters that lie solely within a province's boundaries fall within the constitutional authority of that province. In terms of water use and consumption provincial legislative powers include areas of flow regulation; authorization of water use development; water supply; and thermal and hydroelectric power development.

The provincial government of Ontario uses legislative and non-legislative mechanisms, such as policies and guidelines, to regulate water use and consumption in the province. The Ontario Ministry of the Environment administers those related to environmental management of water, and the Ministry of Natural Resources has some responsibility for regulating those that relate to provincial parks, forests, fish, wildlife, and Crown lands and waters, as well as public safety and emergency response in the case of forest fires, floods and drought.

Civil Code of Québec and Permits for water

Under the Civil Code of Québec, surface and underground water is something that is of common use to all, barring any rights to use or limited appropriation rights that may be recognized. This “common to all” status implies that all members of society have the right to access water and use it in a manner consistent with its nature. This also imples that the government has a responsibility to regulate water use, establish priority uses and preserve its quality and quantity, in the general public interest.